The present invention is directed to a closed cycle gas-cooled nuclear power plant including a high-temperature nuclear reactor, a gas turboset, heat exchange apparatus consisting of recuperators, pre-coolers and intermediate coolers, and a conduit system for conducting the gas coolant through the individual components of the plant and, more particularly, it is directed to the arrangement of the plant within a prestressed concrete pressure tank (cycle-tank construction). Closed cycle plants have an obvious advantage over nuclear power plants of the type where the energy is given off in a secondary cycle, since they combine the simplicity and good output of single circuit plants with the advantages of gas turbines. By arranging the nuclear reactor, the gas turboset and the other cycle components in a common pressure tank (integrated construction), special connecting elements are avoided between individual parts of the plant through which the gas coolant flows and, as a result, a very favorable effect is obtained in the construction and operation of high-temperature reactors. Therefore, an integrated construction is preferred in a number of special nuclear power plant types.
In DAS 1, 156, 903 a power engine unit of the above type is disclosed which is used for vehicles and has a very compact design. In the turboset, the turbine and compressor are located on opposite sides of the reactor core and the common shaft is hollow and extends through the reactor core and the intermediate coolers are located in the annular space between the reactor core and the pressure tank wall. This compact design is based on the consideration that the turbine does not require attendance and, as a result, the turbine and the other cycle components cannot be disassembled.
A similar design of the nuclear reactor is contained in DOS 2,005,208, however, in that arrangement a pressure blanket is provided inside the pressure tank which is open at its end faces and is spaced from the inner wall of the tank in such a way that the heat exchanger is accommodated in the space formed.
In DOS 2,028,736 a closed cycle gas-cooled nuclear power plant is described. The power plant is of the two-tank type with the gas turbine and other components of the gas cycle positioned in a machine block formed of prestressed concrete and separated from the concrete pressure tank to afford a simpler construction of the charging and regulating unit.
A similar design of the concrete pressure tank is illustrated in DAS 1,614,610 in which two closed pressure-proof chambers are provided, with one of the chambers containing the reactor and the other serving as a containment for the remaining power plant equipment. The working medium is carried in lines which penetrate through a partition between the two pressure-proof chambers passing from the reactor to the turbine to the compressor and then back into the annular space below the reactor core. This so-called igloo-construction is technically difficult to realize and the nuclear power plant is very uneconomical, because of the manner in which it is arranged.
In DOS 2,062,934 another gas-cooled nuclear reactor is shown in an integrated construction with the gas turbine arranged in a cavity in the wall of the pressure tank surrounding the reactor core. By means of a bypass, a portion of the cold gas coolant for the reactor core can be bypassed about the core and mixed directly with the hot gas coolant issuing from the core.
In still another nuclear power plant of the above-described type as set forth in DOS 1,764,248 the nuclear reactor and all of the coolant cycle components are arranged in closely spaced parallel vertical bores within the concrete pressure tank and the components are accessible from the exterior and passageways are provided for the cooling medium in the wall of the pressure tank and between the individual vertical bores. However, in this arrangement the cooling medium must traverse very long flow paths and the plant requires a relatively large pressure tank.